A considerable amount of scrap metal that is generated as a result of metal machining in industries today is in the form of ductile milling stringers. The stringers are continuous ribbons of metal which have been sheared off by a milling/cutting operation on ductile metal stock. The stringers are not easily broken due to their ductility and therefore form long curled ribbons which, when heaped together as scrap, form an entangled commodity with a very low packing density.
Such ductile tangled millings have been consistently downgraded in economic value due to their limited utility. Batches of such scrap material have been used in ladles or ingot vessels as a cushion for dropping heavy solid scrap thereon which, in turn, protects the refractory lining of such ladles or vessels. Such scrap has also been alternatively hot pressed into a bale which removes the oils from such milling scrap so that the bale can be fed as a raw ferrous material to an electric furnace for melting. Apart from such uses, the scrap has almost no value. Attempts to use such scrap for making powder metal have not met with success. This is principally due to the fact that in attempting to comminute the stringers, they become jammed in a hammer mill or other pulverizing device. Such jamming, of course, results from their ductility which inhibits fracture. Moreover, the tangled scrap usually has foreign debris mixed into it as a result of loose scrap keeping habits. Such debris usually consists of large pieces of solid metal which damage the pulverizing or comminuting device rather easily.
What is needed is a method that can economically convert such entangled ductile milling ribbons to a usable metal commodity without the necessity of melting so that it can be directly recycled for use in making metal products.